JP2003329816A - Bean splitter and laser marking device mounted therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple optical system which can generate a plurality of beams of the same intensity from a laser beam and a laser marking device which is mounted therewith and can emit a plurality of line light beams at a low cost. <P>SOLUTION: The beam splitter is configured by combining two triangular prisms having base surface shapes each consisting of a rectangular isosceles triangle and thin films for separating incident light to intensity of respectively 50% are formed on the planes inclusive of the ridgelines of the respective rectangular isosceles triangles. Further, the rectangular isosceles triangles are combined to configure a beam splitter. A beam of the incident light is reflected by the light separation surface and the other is transmitted therethrough. Further, a beam of the reflected light is transmitted through the other light separation surface and a beam thereof is reflected by the same. Similarly, a beam of the transmitted light is transmitted through the other light separation surface and a beam thereof is reflected by the same. By the above principle, the light incident on the beam splitter is separated to four orthogonal directions. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates mainly to a beam splitter for splitting one laser beam into a plurality of laser beams, and further using the beam splitter for indoor and outdoor house construction work and the like. The present invention relates to a laser marking device used for marking operation at that time.

[0002]

2. Description of the Related Art At the time of building a house, especially at the start of construction work, it is essential to set a standard for mounting various members and to set a standard line for positioning of member processing, that is, marking out.
Therefore, at the construction site, leveling was performed using an instrument such as a level surveying instrument, a plurality of mark inks were attached to the wall of the target structure, and these were connected to form a marking line, which was the construction standard.

However, this work needs to be performed by at least two people, which is very troublesome and inefficient. In order to improve this problem, in recent years, it has become more frequent to efficiently perform marking out using a laser marking out device having a line light irradiation function. Since the laser marking device can easily perform marking work by one person, it is becoming an essential construction work tool for construction work.

A so-called "tachi line" that draws a vertical line from the floor to the wall to the ceiling, or two "tachi lines" that are radiated at the same time, are used to draw a right angle line on the ceiling. (Ogane line), a horizontal line that draws a horizontal line on the wall, or a ground line that irradiates a laser beam focused on the floor directly below the laser marking device.

In order to improve the efficiency of the marking-out work using the laser marking-out device, it is desired that one laser marking-out device can irradiate a plurality of marking-out lines. So recently
A device capable of irradiating two or more lines with one device is being proposed.

Conventionally, as a method of irradiating a plurality of lines from one laser marking device, a method of using a plurality of laser light sources and a method of dividing a laser beam emitted from one laser light source The method of obtaining is known.

[0007]

In the former method, there is a problem that the cost of the apparatus increases as the number of laser light sources mounted increases. On the other hand, the latter method of obtaining a plurality of line lights by splitting the laser light is, for example, as disclosed in JP-A-9-159451, emission of a structure in which a plurality of half mirrors are laminated in series in the laser emission direction. There is a system that uses an optical system. However, in this method, the intensity of light transmitted through the first half mirror is reduced to 1/2, and the intensity of light transmitted through the second half mirror is further reduced to 1/2. In this way, the light intensity decreases sequentially each time it passes through the half mirror, so it is possible to obtain multiple beams by using the disclosed optical system, but the light intensity greatly differs for each divided beam. , The brightness of the obtained plurality of line lights is different from each other. Further, since it is necessary to arrange a plurality of half mirrors in order to divide the beam, there is a problem that the optical system becomes complicated and the number of parts of the optical element increases.

Therefore, many conventional laser marking devices capable of irradiating a plurality of line lights have a structure provided with laser light sources corresponding to the number of line lights. However, in this case, as described above, the device price increases as the number of light sources increases. Therefore, in order to perform the work with higher efficiency in the marking operation, an expensive device is required.

An object of the present invention is to provide a beam splitter and a laser marking device equipped with the beam splitter which solves the above conventional problems. Specifically, it is to provide a simple beam splitter that can generate a plurality of beams having the same intensity from one laser beam and a laser marking device that can irradiate a plurality of lines of light at a low cost.

[0010]

In order to achieve the above object, the beam splitter of the present invention is a light for dividing light into reflected light and transmitted light in order to obtain a plurality of separated lights from one incident light. One feature is that it has two or more separation surfaces. With this configuration, four beams can be easily generated, and the laser marking device using this can irradiate four line lights from a single light source.

Another feature of the present invention is that the beam splitter is formed by combining two or more transparent triangular prisms, and at least one of the side surfaces of the triangular prism including the two sides sandwiching the apex angle in the bottom shape of the triangular prism. The light separating surface is formed. With this structure, it is possible to generate light beams in four directions that are orthogonal to each other. Further, by slightly deforming the shape of one triangular prism, the angle of the emitted beam can be changed instead of the right angle.

Another feature of the present invention is that the beam splitter is configured by combining a transparent triangular prism and a transparent quadrangular prism, and at least one of the side surfaces of the triangular prism including the two sides sandwiching the apex angle in the bottom shape of the triangular prism. And a light separating surface is formed on at least one of the side surface and the connecting surface of the quadrangular prism facing the connecting surface with the triangular prism. In any of these configurations, the beam splitter can be configured by combining only triangular prisms and quadrangular prisms, so that the structure can be simple and compact. Moreover, it is possible to generate a light beam in three directions perpendicular to each other.

Another feature of the present invention is that the beam splitter is constructed by combining two transparent quadrangular prisms and two transparent triangular prisms, and the side surface of the quadrangular prism facing the joining surface with the other quadrangular prism. And a light separating surface is formed on the joint surface or one of the surfaces. With this configuration, it is possible to easily generate two light beams in two directions at right angles.

Another aspect of the present invention is that the beam splitter has a first semi-transparent surface, a second semi-transparent surface, and a third semi-transparent surface. The first surface separates the light into first reflected light and first transmitted light that are perpendicular to each other, and the second surface separates the first reflected light from the second reflected light and the second transmitted light that are perpendicular to each other. It is configured such that the first transmitted light is split into light and the third surface splits the first transmitted light into third reflected light and third transmitted light.

With this configuration, the first, second and third
By appropriately setting the angle of the surface of, the four incident lights that are orthogonal to each other can be obtained from the one incident light. Further, by making the second or third surface parallel to the first surface, it is possible to generate four light beams in three directions perpendicular to each other. Further, by making the first surface parallel to the second and third surfaces, it is possible to generate four light beams in two directions at right angles. Hereinafter, specific embodiments of the present invention will be described in detail.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIGS. 1 and 2 are basic configuration diagrams showing an embodiment of a beam splitter of the present invention. The beam splitter 1 is configured by combining three triangular prisms each having a bottom face shape of an isosceles right triangle. The triangular prism is made of glass or plastic capable of transmitting light. In this embodiment, as a prism material
BK7 was used. The size of one triangular prism-shaped element forming the prism is as follows. The length of one side of the right-angled isosceles triangle that forms the bottom surface of the triangular prism is 3 mm, and the height is 5 mm.
Is. A dielectric thin film for separating incident light into transmitted light and reflected light is formed on the light separation surface 2. The film thickness of the dielectric thin film is adjusted so that the transmitted light and the reflected light have the same light intensity.

As shown in FIG. 3, the light B1 (the light source is not shown) that is incident from the incident surface of the beam splitter 1 is reflected by the light separating surface 2a and becomes one of the reflected light B2.
The other is transmitted and becomes transmitted light B3. The light separation surface 2a evenly separates the transmitted light intensity and the reflected light intensity by 50%. One of the reflected lights B2 becomes the transmitted light B21 and the other becomes the reflected light B22 by the next light separating surface 2b. Since the light separation surface 2b uniformly separates the transmitted light intensity and the reflected light intensity by 50%, the transmitted light B21 and the reflected light B22 have an equal intensity of 25% each compared to the intensity of the incident light B1. It becomes separated light. Similarly, the transmitted light B3 becomes the transmitted light B31 and the other reflected light B by the other light separation surface 2c.
32. Since the light separation surface 2c uniformly separates the transmitted light intensity and the reflected light intensity by 50%, the transmitted light B31
And the reflected light B32 is 2 times greater than the intensity of the incident light B1.
It results in a uniform split light with an intensity of 5%. That is, the beam splitter 1 can split the incident light B1 into four orthogonal directions and can equalize the light intensity of each split light. (Embodiment 2) FIG. 4 shows another embodiment of the present invention, in which the light transmitted and reflected by the beam splitter 1 can be emitted in a desired direction rather than in mutually orthogonal directions. That is, in the beam splitter 1 shown in the first embodiment, the light B1 incident on the beam splitter 1
Are separated into four directions orthogonal to each other as shown in FIG. 3, for example, the light splitting surface 2a of the beam splitter 1 is separated.
The direction of reflected light can be changed by changing the size of the included angle between 2 and 2c. In this embodiment, as shown in FIG. 4, an example in which the size of the included angle between the light separation surfaces 2a and 2c is set to be smaller than 90 degrees is shown. According to this structure, the emission direction of the reflected light B32 approaches the incident light B1. Figure 4
On the contrary, the angle between the light separating surfaces 2a and 2c is 90
If it is larger than the degree, the direction of the reflected light B32 is the incident light B1.
Stay away from. Similar results can be obtained when the angle between the light separation surfaces 2a and 2b is changed. In addition, it is possible to change the direction of the separated light in various ways by changing the combination of the elements that form the beam splitter 1. (Embodiment 3) FIG. 5 shows another embodiment of the present invention, which is an example in which the beam splitter is constituted by four triangular prisms. In this embodiment, the beam splitter 1
The light B1 (light source not shown) incident from the incident surface of 1 is reflected by the light separating surface 2a to become reflected light B2, and the other is transmitted to become transmitted light B3. The transmitted light B3 is emitted from the end surface of the beam splitter 1 as it is, and becomes the transmitted light B31. One of the reflected lights B2 becomes the transmitted light B4 and the other becomes the reflected light B22 by the next light separating surface 2b. One of the transmitted light B4 is transmitted by the next light separation surface 2c.
1 and the other becomes reflected light B42. With this configuration, it is possible to generate four light beams in three directions perpendicular to each other. (Embodiment 4) FIG. 6 shows another embodiment of the present invention, which is an example in which the beam splitter is composed of three triangular prisms and one quadrangular prism. In the case of this embodiment, the light B1 incident from the incident surface of the beam splitter 1 (the light source is not shown)
Is reflected by the light splitting surface 2a, and one of them is reflected light B2.
And the other is transmitted and becomes transmitted light B3. Reflected light B2
Is the transmitted light B21 due to the next light separation surface 2b,
The other becomes reflected light B22. Similarly, the transmitted light B3 becomes the transmitted light B31 and the other becomes the reflected light B32 by the other light separation surface 2c. With this structure, four light beams can be generated in three directions perpendicular to each other. (Embodiment 5) FIG. 7 shows another embodiment of the present invention, which is an example in which a beam splitter is composed of three triangular prisms and one quadrangular prism. In the case of this embodiment, the light B1 (the light source is not shown) that is incident from the incident surface of the beam splitter 1 is reflected by the light separation surface 2a to become reflected light B2, and the other is transmitted and transmitted light B3. Becomes One of the reflected lights B2 becomes the transmitted light B21 and the other becomes the reflected light B22 by the next light separating surface 2b. Similarly, the transmitted light B3 becomes the transmitted light B31 and the other becomes the reflected light B32 by the other light separation surface 2c. Even with such a configuration, four light beams can be generated in three directions perpendicular to each other as in FIGS. (Embodiment 6) FIG. 8 shows another embodiment of the present invention, which is an example in which a beam splitter is composed of two triangular prisms and two quadrangular prisms. In the case of this embodiment, the light B1 (the light source is not shown) that is incident from the incident surface of the beam splitter 1 is reflected by the light separation surface 2a to become reflected light B2, and the other is transmitted and transmitted light B3. Becomes One of the reflected lights B2 becomes the transmitted light B21 and the other becomes the reflected light B22 by the next light separating surface 2b. Similarly, the transmitted light B3 becomes the transmitted light B31 and the other becomes the reflected light B32 by the other light separation surface 2c. With this structure, four light beams can be generated in two directions at right angles. By changing the angles of the light splitting surfaces 2 of the various beam splitters 1 shown in the above embodiments, it is possible to change the light emission direction and the light emission angle at the same time. (Embodiment 7) Next, a method of manufacturing the beam splitter 1 of the present invention will be described with reference to FIGS. First, three transparent triangular prisms, that is, triangular prisms 1a, 1
Prepare b and 1c. Although three sizes are drawn the same in this figure, actually, the triangular prisms 1a and 1b have the same size, and 1c has a shape slightly larger than this. Next, a thin film for transmitting and reflecting light at an appropriate ratio is formed on the surface of the surface including the two sides 2a and 2b that sandwich the apex angle of the two triangular prisms 1a and 1b.

The material of the thin film may be any as long as it transmits and reflects light, but generally a dielectric thin film is often used. The thickness of the thin film is appropriately selected according to the ratio of light transmission and light reflection. Next, a thin film was formed as shown in FIG.
This is completed by combining the individual triangular prisms 1a and 1b and another triangular prism 1c and adhering them. An ordinary adhesive may be used for the adhesion, but an intermolecular force generated on the bonding surfaces when the smooth surfaces are combined may be used. (Embodiment 8) Next, an embodiment in which the beam splitter 1 of the present invention is mounted on a laser marking device will be described. Figure 1
As shown in FIG. 1, the laser marking device 9 basically comprises an optical system 4 for generating line light and a support mechanism 5 for keeping the optical system horizontal. FIG. 12 shows an outline of the line light generating optical system 4. The laser beam B0 emitted from the semiconductor laser 6 is converted by the collimator lens 7 into collimated light (parallel light) B1 having a circular beam cross-sectional shape. In this embodiment, the beam diameter of the collimated light B1 is 2 m.
It is set to be m. Next, the collimated light B1 passes through the beam splitter 1 of the present invention and four beams B2
It is separated into 1, B22, B31 and B32. These four laser beams have an intensity of 25% of the incident light intensity, and each beam has a circular beam cross section and a beam diameter of 2 m.
m collimated light. The separated lights B31 and B2
2 and the separated lights B32 and B21 are not on the same straight line, for example, a transparent rectangular parallelepiped optical element, that is, a light emitting position adjusting element 8 is installed in the vicinity of the beam splitter 1 of the present invention to adjust the light emitting position. To do. B32 and B22
The optical path is slightly changed by the light emitting position adjusting element 8. As a result, B31 and B22 are positioned on the same line in the vertical direction,
B32 and B21 are located on the same straight line in the horizontal direction.

FIG. 13 shows a principle diagram in which the optical path is changed by the light emitting position adjusting element 8. When light is incident on the light emitting position adjusting element 8 having a refractive index of n from the air having a refractive index of 1 at 45 °, 1 × sin 45 = n × sin θ based on the principle of refraction.
The light is refracted at an angle of θ, goes straight inside the device, and exits at an angle of 45 °. Now, if the length of light traveling inside the element is L,
The positional shift amount h at the time of light emission is represented by h = Lsin (45−θ). If the thickness of the element is b, then b = Lcos θ, so the element thickness required to correct the amount of deviation of h is b
= Hcos θ / sin (45−θ). The direction of light may be changed by using, for example, a mirror as the light emitting position adjusting element 8.

Returning to the explanation of FIG. 12, the separated lights B21,
B22, B31 and B32 are converted into line light by passing through glass rod lenses 21, 22, 31 and 32 which are a kind of line light generating optical element. The direction of the generated line light is defined by the installation direction of the rod lens. That is, the rod lens is arranged in the vertical direction to obtain horizontal line light, and the rod lens is arranged in the horizontal direction to obtain vertical line light. In this embodiment, the rod lens
21, the rod lens 22 and the rod lens 32 are arranged horizontally, and further the rod lens 31 is arranged vertically, so that the B21, B22 and B32 lights are converted into the vertical line light 10 and the B31 light.
Is converted into horizontal line light 11.

[0021]

As described above, by using the beam splitter according to the present invention, one laser beam can be separated into a plurality of laser beams by a simple method. Further, by mounting the beam splitter according to the present invention in the optical system of the laser marking device, it is possible to easily obtain a plurality of laser beams from one light source, so that a plurality of marking laser lines can be produced at low cost. It has become possible to generate light. As a result, it has become possible to obtain a laser marking device for multi-line light irradiation, which has been very expensive in the past, at a low price.

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of a beam splitter of the present invention.

FIG. 2 is a plan view of the beam splitter shown in FIG.

FIG. 3 is a plan view showing an embodiment of a beam splitter of the present invention.

FIG. 4 is a plan view showing another embodiment of the beam splitter of the present invention.

FIG. 5 is a plan view showing another embodiment of the beam splitter of the present invention.

FIG. 6 is a plan view showing another embodiment of the beam splitter of the present invention.

FIG. 7 is a plan view showing another embodiment of the beam splitter of the present invention.

FIG. 8 is a plan view showing another embodiment of the beam splitter of the present invention.

FIG. 9 is a schematic view showing a method for manufacturing a beam splitter of the present invention.

FIG. 10 is a schematic view showing a method for manufacturing a beam splitter of the present invention.

FIG. 11 is a schematic view of a laser marking device equipped with the beam splitter of the present invention.

FIG. 12 is a schematic configuration diagram showing an embodiment of a laser marking device equipped with a beam splitter of the present invention.

FIG. 13 is an explanatory diagram for explaining the correction of the emission position by the light emission position adjustment element.

[Explanation of symbols]

1: Beam splitter 1a, 1b, 1c: triangular prism 2: Light separation surface 2a, 2b, 2c: Light splitting surface 4: Line light generation optical system 5: Support mechanism 6: Semiconductor laser 7: Collimating lens 8: Light emitting position adjusting element 9: Laser marking device 10: Vertical line light 11: Flat line light 21, 22, 31, 32: Rod lens

Claims (19)

[Claims] 1. A beam splitter for obtaining a plurality of separated lights from a single incident light, which has two or more light separation surfaces for separating the light into reflected light and transmitted light. . 2. A light separating surface is formed on at least one side surface of a triangular prism including two sides sandwiching an apex angle in a bottom surface shape of the triangular prism, which is formed by combining two or more transparent triangular prisms. The beam splitter according to claim 1. 3. The beam splitter according to claim 2, wherein the bottom surface of the triangular prism is an isosceles right triangle. 4. A light separating surface is formed on at least one side surface of a triangular prism including two sides sandwiching an apex angle in the bottom shape of the triangular prism, which is formed by combining a transparent triangular prism and a transparent quadrangular prism. The beam splitter according to claim 1, wherein a light splitting surface is formed on at least one of the side surface and the bonding surface of the quadrangular prism facing the bonding surface with the triangular prism. 5. A combination of two transparent quadrangular prisms and two transparent triangular prisms, wherein the quadrangular prism has a side surface facing the joint surface with the other quadrangular prism and the joint surface or any one of the side surfaces. The beam splitter according to claim 1, wherein a light splitting surface is formed on the surface. 6. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface, wherein light from a light source is perpendicular to each other by the first surface. Of the reflected light and the first transmitted light, the second surface separates the first reflected light into the second reflected light and the second transmitted light which are orthogonal to each other, and the third surface separates the first reflected light from the second reflected light. A beam splitter, characterized in that by separating the transmitted light of 1 into a third reflected light and a third transmitted light, four outgoing lights that are orthogonal to each other can be obtained from one incident light. 7. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface, wherein light from a light source is perpendicular to each other by the first surface. Of the first reflected light and the first transmitted light are separated by the second surface into the second reflected light and the second transmitted light which are perpendicular to each other. , The third surface separates one of the second reflected light and the second transmitted light into a third reflected light and a third transmitted light that are at right angles to each other, so that at least a right angle of 3 A beam splitter characterized by obtaining four outgoing lights in the direction. 8. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface parallel to the first surface.
The light from the light source is separated by the first surface into first reflected light and first transmitted light which are perpendicular to each other, and the second surface separates the first reflected light from the second reflected light and the first reflected light which are perpendicular to each other. By separating the first transmitted light into the third reflected light and the third transmitted light by the third surface, it is possible to separate the first transmitted light from the first incident light into at least three orthogonal directions. A beam splitter that obtains the emitted light of a book. 9. A first semitransparent surface, a second semitransparent surface parallel to the first surface, and a third semitransparent surface parallel to the first surface. , The light from the light source is separated into first reflected light and first transmitted light which are perpendicular to each other by the first surface, and the first reflected light is separated into second reflected light which is perpendicular to each other by the second surface. By separating into the second transmitted light and the above-mentioned first transmitted light into the third reflected light and the third transmitted light by the third surface,
A beam splitter that obtains four outgoing lights in at least two orthogonal directions from one incoming light. 10. A beam splitter having two or more light splitting surfaces for splitting the incident light into reflected light and transmitted light in order to obtain a plurality of separated lights from one incident light, and the beam splitter. A semiconductor laser that generates incident light,
An optical system for converting a plurality of light beams emitted from the beam splitter into line light, and a laser marking device. 11. The beam splitter according to claim 10, wherein the beam splitter is formed by combining two or more transparent triangular prisms.
A laser marking device, wherein a light separating surface is formed on at least one side surface of a triangular prism including two sides sandwiching an apex angle in a bottom shape of the triangular prism. 12. The laser marking apparatus according to claim 11, wherein the beam splitter has a triangular prism whose bottom surface is an isosceles right triangle. 13. The beam splitter according to claim 10, wherein the beam splitter is formed by combining a transparent triangular prism and a transparent quadrangular prism, and at least one of side surfaces of the triangular prism including two sides sandwiching an apex angle in a bottom shape of the triangular prism. A laser marking device characterized in that a light separating surface is formed on a surface, and a light separating surface is formed on at least one of the side surface and the bonding surface of the quadrangular prism facing the bonding surface with the triangular prism. 14. The beam splitter according to claim 10, wherein the beam splitter is formed by combining two transparent quadrangular prisms and two transparent triangular prisms, and the quadrangular prism faces a joining surface of the other quadrangular prism. A laser marking device, characterized in that a light separating surface is formed on a side surface and / or the bonding surface. 15. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface, wherein light from a light source is perpendicular to each other by the first surface. Of the reflected light and the first transmitted light, the second surface separates the first reflected light into the second reflected light and the second transmitted light which are orthogonal to each other, and the third surface separates the first reflected light from the second reflected light. By separating the transmitted light of No. 1 into the third reflected light and the third transmitted light, a beam splitter configured to obtain four outgoing lights orthogonal to each other from one incoming light, and a beam splitter 1. A laser marking device, comprising: a semiconductor laser that generates incident light; and an optical system that converts at least one of four lights emitted from the beam splitter into line light. 16. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface, wherein light from a light source is perpendicular to each other by the first surface. Of the first reflected light and the first transmitted light are separated by the second surface into the second reflected light and the second transmitted light which are perpendicular to each other. , The third surface separates one of the second reflected light and the second transmitted light into a third reflected light and a third transmitted light that are at right angles to each other, so that at least a right angle of 3 A beam splitter configured to obtain four outgoing lights in a direction, a semiconductor laser that emits light incident on the beam splitter, and at least one of the four lights outgoing from the beam splitter is converted into line light A laser marking device, which comprises: 17. A first semitransparent surface, a second semitransparent surface, and a third semitransparent surface parallel to the first surface.
The light from the light source is separated by the first surface into first reflected light and first transmitted light which are perpendicular to each other, and the second surface separates the first reflected light from the second reflected light and the first reflected light which are perpendicular to each other. By separating the first transmitted light into the third reflected light and the third transmitted light by the third surface, it is possible to separate the first transmitted light from the first incident light into at least three orthogonal directions. Beam splitter configured to obtain the emitted light of a book, a semiconductor laser that emits light incident on the beam splitter, and an optical system that converts at least one of the four lights emitted from the beam splitter into a line light And a laser marking device. 18. A first semitransparent surface, a second semitransparent surface parallel to the first surface, and a third semitransparent surface parallel to the first surface. , The light from the light source is separated into first reflected light and first transmitted light which are perpendicular to each other by the first surface, and the first reflected light is separated into second reflected light which is perpendicular to each other by the second surface. Separation into the second transmitted light, and by separating the first transmitted light into the third reflected light and the third transmitted light by the third surface, at least two orthogonal directions from one incident light are obtained. A beam splitter configured to obtain four emitted lights, a semiconductor laser that generates light incident on the beam splitter, and an optical that converts at least one of the four lights emitted from the beam splitter into line light A laser marking device comprising a system. 19. The laser according to claim 6, further comprising an optical element for adjusting a laser beam emission position provided between the beam splitter and the line light generating optical system. Inking device.